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name: connect-go-reference description: Reference the LOCAL connect-go/ directory for ConnectRPC protocol. NEVER use WebFetch/WebSearch for github.com/connectrpc/connect-go - always read local files.

connect-go-reference

Reference the LOCAL connect-go/ directory for understanding the ConnectRPC protocol.

CRITICAL: Use Local Files Only

NEVER fetch from GitHub. Do not use:

• WebFetch with github.com/connectrpc/connect-go
• WebFetch with raw.githubusercontent.com/.../connect-go
• WebSearch for "connect-go" implementation details

ALWAYS use local files:

• Read tool with connect-go/*.go paths
• Grep tool with path="connect-go/"
• Glob tool with path="connect-go/"

The connect-go/ directory at the repository root is the authoritative reference.

Instructions

The connect-go/ directory at the repository root contains the official Go implementation of the ConnectRPC protocol.

Setup (one-time only)

If the directory doesn't exist, clone it once:

git clone https://github.com/connectrpc/connect-go.git connect-go

After cloning, ALWAYS use the local files via Read/Grep/Glob tools.

Key Files Reference

File	Purpose
protocol_connect.go	Connect protocol implementation (unary + streaming)
protocol_grpc.go	gRPC protocol implementation
protocol.go	Protocol abstraction and detection
envelope.go	Frame/envelope encoding (5-byte header)
client.go	Client-side implementation
handler.go	Server-side handler implementation
client_stream.go	Client streaming logic
handler_stream.go	Server streaming logic
error.go	Error types and code mappings
codec.go	Protobuf/JSON codec interfaces
compression.go	Compression support (gzip, etc.)
duplex_http_call.go	HTTP call abstraction for streaming
option.go	Configuration options

Usage Patterns

Protocol detection logic:

Read connect-go/protocol.go and connect-go/protocol_connect.go for Content-Type parsing

Streaming frame format:

Read connect-go/envelope.go for the 5-byte envelope format:
[flags: 1 byte][length: 4 bytes BE][payload]

Error handling:

Read connect-go/error.go for error codes, wire format, and detail encoding

gRPC trailers:

Read connect-go/protocol_grpc.go for grpc-status header and trailer handling

When to Use

• Implementing new protocol features
• Debugging wire format or encoding issues
• Verifying correct behavior against reference
• Understanding edge cases in streaming
• Checking error code mappings

How to Use (Examples)

# Search for content-type handling
Grep pattern="Content-Type" path="connect-go/"

# Read specific file
Read file_path="connect-go/protocol_connect.go"

# Find all error-related code
Grep pattern="Code" path="connect-go/error.go"

FORBIDDEN:

• WebFetch("https://github.com/connectrpc/connect-go/...") - NO
• WebFetch("https://raw.githubusercontent.com/connectrpc/connect-go/...") - NO
• WebSearch("connect-go ...") for implementation details - NO
• Guessing behavior without reading local connect-go/*.go files - NO